Tube-coupling for pneumatic-despatch systems and the like



vA. w. PEARSALL. l TUBE COUPLINGFOR PNEUMATIC DESPATCH SYSTEMS AND THE LIKE.

APPLICATION FILED FEB-17|I9I9.

'I I I I l Patented Nov. 2, 1920.

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ALBERT W. PEARSALL, OF LOWELL, MASSACHUSETTS, ASSIGNOR TO THE LAMSON COMPANY, OF BOSTON, MASSACHUSETTS, A CORPORATION OF NEW JERSEY.

TUBE-COUPLING FOR PNEUMATIC-DESPATCH SYSTEMS AND THE LIKE.

Speecaton of Letters Patent.

Patented Nov. 2, 1920.

Application led February 17, 1919. Serial No. 277,641.

To all laU/1.0m it may concern.' Y

Be it known that I, ALBERT4 W. PEARsALL, a citizen of the United States of America, and resident of Lowell, in the county of Middlesex and State of Massachusetts, have invented new and useful Improvements in Tube-Couplings for Pneumatic-Despatch Systems and the like, of which the following is a specification.

The present invention relates to pipe couplings and more particularly to couplings for connecting together the tubes in a pneumatic despatch system of the type adapted to convey cash boxes or other articles.

In systems of the aforesaid character many peculiar diiiiculties are presented. The tubes are made of thin metal, usually either brass or aluminum, and-are therefore not adapted to be clamped very tightly or to have screws or other fastening means secured therein. This is particularly true when the tubes are made of aluminum; and moreover aluminum is not adapted to be soldered lor welded. Furthermore, in installing such systems it is usually necessary to cut the tubes at the place where the system is installed, in order to tit the system into the peculiar circumstances of the place, and it is therefore impracticable to form fianges or the like at the ends of the tubes when they are manufactured. Pneumatic systems should be substantially air-tight in order to prevent the leakage of air, into the system in case of a vacuum system and out of the system in the case of a pressure system. Furthermore there are several factors peculiar to systems of the character referred to which tend to separate the tube sections. The carriers passing through the system rub and strike against the walls of the tubes tending to loosen and separate them. Where a joint is followed by a bend in the tubing the joint is especially liable to loosening due to the impact of the carriers against the bend. Tf the tubes do not match accurately at their abutting ends the carriers strike against the edges of the tubes and not only tend to cut the carrier runners but Valso tend to s te the tubes.v

Another problem presentedV by pneumatic despatch systems is the elimination of the noise produced by the carriers passing through the tubes. The carriers are'usually encircled with bands of felt or the like at their ends to reduce the noise and coperate with the usually satisfactory where the tubes are smooth and continuous on the inside. However, if there are annular recesses on the inner periphery of the tubing, as e. g., where the juxtaposed ends of two adjoining tubes have separated a small amount, the carrier strikes the forward shoulder thus presented by the recess and, even where the carriers are fitted with vfelt heads and sealing disks behind the felt heads or the like, the impact produces an objectionable noise. Indeed, the felt heads or runners fitted with the sealing disks expand into the annular recesses and accentuate the noise. And this action obviously tends unduly to wear the carriers and Vfurther to separate the tubes. Similar effects result from any annular recesses on the inner periphery of the tubing, as e. g., the recesses formed by striking up annular beads near the ends of the tubes to couplings employed to hold the tubes together.

The objects of the present invention are to overcome the aforesaid difficulties and more particularly to provide a coupling which is particularly adapted to light tubing of aluminum or other material, which will prevent the tubes from separating even under severe conditions of usage, which is relatively noiseless, which is air-tight, which can be easily and quickly applied even by unskilled workmen, which permits a section of the tubing to be removed without disturbing adjacent sections, and which affords other advantages as will hereinafter appear.

In the accompanying drawings which illustrate two preferred embodiments of my invention,- j

Figure l is a central longitudinal section of one embodiment of the invention;

Fig. 2 is a central longitudinal section of the other embodiment; and

Fig. 3 is a transverse section on the line 3-8 of Fig. l. l The particular embodiment of the invention illustrated in Fig. l comprises an inner sleeve S surrounding the juxtaposed ends of the two tubes T and T', an outer sleeve S surrounding the inner sleeve S and extend ing beyond` theV sleeve S in both directions, and a plurality of clamping rings R for securing the ends of the outer sleeve S to the tubes T and T respectively, the rings being divided and having bolts B for drawing the ends together. The tubes T and T are proof the sleeve yvidedwith annular rows Vof protuberancesVA P -on their outer periplieries to cooperate with the clamping rings to secure'tlie ends to the tubes.

The sleeve-S is `preferably `coi'itinuous cir cumferentially in which case Vit is placedn over the tubes-by slipping it over the end of one tube and then slipping tlierothertube thereinto so that the'two tubes abut in the central transverse region of the' tube. The sleeve S, which preferably -iits snuglyV Y around the endsof the tubes, may 'be formed of the same material Vas the tubes, c. g., brass Y or aluminum, or of any othersuitable mais' terial.

The sleeve S is formed of a sheetof ma te'rial and is wound around the tubes after .the Vsleeve S has been `fitted upon the tubes, the ends of the sheet preferably overlapping as shown inFig. 3. rPhe sheet of material of which the sleeve S is formed is prefer-V Vthe tubes.V For a purposewhichwill hereinafter be explained the area of the indentations is relatively small and the indentations are spaced' apart. The indentations are preferably made at the time the tubes are fittedftogether, after Vthe tubes have 'Y been cut to theproper length,but may readily beV Vmade'in tubes already installed without removing the tubes from their supports. The indentations may readily be formed by meansV of a piiicei-lilretool which hastwo arms pivoted together, 'one arm extending inside the tube and one arm extending outside the tube and the toolfbeing provided Vwith a stop adapted to engage the end vof the tube `so that when the two arms are Yforced together an indentation will be formed at a predetermined distance fromV the end of the tube.

The embodiment illustrated in Fig. 2 is Vsimilar to that shown in Fig. l in that it comprises an inner sleeve S,and outer sleeve S", and clamping ringsR lforc'onnecting the Y two tubes Tandv T togetheigfthe vtubes being Jes provided withprotuberances `Pas in Fig. l;

However Y at the right-hand.l end the prof tuberancesP arelocated at the end of the sleeve'S and onlya single clamp ring YVis y employed at thatend of 'the sleeve, the parts Vbeing so arranged that the protuberances restrictthe endwisemovement along the tubes of both the `inner 'and outer sleeves.

` By means o j Y flight tubing of phenumatic despatchV systems maybe readily and 'durably secured tof,

gether. With the doubley sleeve arrangement around the tubes T and T.

portions were made continuous inthe form Y Vsleeve v S may f my improved coupling. the Y alinethe 'connection and render it air-tights while the outer sleeve serves Vprincipally to secure the two tube Ysections together. By virtue of the protuloerances P' the tubes are prevented from pulling apartfwithout clamping the sleeve S suciently tightly to deform the thin tubes'and without solderingor welding the ysleeve to the tubes.

A cardinal feature of the invention resides in the unique formation of the raised portions P which are annularly arranged If these raised of an annular bead, an annular channel would result on the inside of the tube. As hereinbefore explained this would cause the tubes to tend to separate and wouldresult `in excessive noise and `loss of transmission force at the several joints. However, by making theV area of, the indentations P Y relatively small and by spacing the indentations apart a considerable distance all of these faults are overcome. j

Another important feature oftlie'invention in its more V.specific aspect resides in locating the indentations or protuberances P a sulicient distance from the end of the tube at least on one side of the joint, Vto permit thejclesed ring or sleeve S to be slipped along the tube past the joint between the two tubes. In this way a tube section may Ybe taken out or inserted without disturbing the adjoining tube sections. In Fig. lthe be slipped from over the joint J in either direction. Y i i lclaimzl r l'. A coupling for connecting together the raised portions annularly arranged on the Vouter peripheries of said ends,;and a sheet juxtaposed ends of two tubes comprisingv yraised portions annularly arranged on the Vouter periplieri'es ofV said ends, 'a sheet of material wound around said, ends, :and clamps for drawing said sheets inwardly around said tubes adjacent `said ,raised ,por-

tions.

juxtaposed ends of pneumatic tubes V.or the like comprisinga plurality of protubera'nces spaced 'around'the' `outer periphery of each of said ends, said protuberances comprising indentations*struckV up from Ythe tubes, Yand V a sheet ofmaterial wound .around's`aidfendS the end Vof Vsaid sheetbeing drawn down voutside said protu'berances and secured to said tubes respectively. Y

AV coupling 'for connecting together-'the ion ,juxtaposed endsV of two tubes comprising i e. A coupling forconnectingvtogetherthe juxtaposed ends of twoV tubes. comprisin gV a sleeve closely surrounding said ends, a sheet of material wound around said ends over said sleeve, the end of said sheet extending beyond the ends of said sleeve, and means for securing the ends of said sheet to said tubes respectively.

5. A coupling for connecting together the juxtaposed ends of two tubes comprising raised portions annularly arranged on the outer peripheries of said tubes, a sleeve closely surrounding said ends and extending outwardly to said raised portions, and a sheet of material wound around said sleeve and extending over said raised portions, said sheet being drawn down outside said raised portions and secured to said tubes respectively, whereby said raised portions restrict the movement or' both said sleeve and said sheet longitudinally of the tube.

6. The method of joining together the ends of two pneumatic tubes or the like comprising` striking up adjacent the ends of the tubes raised portions annularly arranged, placing a sleeve over said ends of the tubes, and clamping the sleeve to the tubes outside said raised portions.

7. The method of joining together the ends of two pneumatic tubes or the like comprising striking up an annular row of protuberances adjacent the end of each tube, placing a sleeve over said ends of the tubes, and clamping the sleeve to said tubes outside said rows of protuberances.

8. The method. of joining together the ends of two pneumatic tubes or the like comprising striking up an annular row of protuberances adjacent the end of each tube, wrapping a sheet of material around said ends, and clamping said sheet to said tubes outside said protuberances.

9. The method of joining together the ends of two pneumatic tubes or the like comprising striking up an annular row of protuberances adjacent the end of each tube, fitting a continuous sleeve over said ends between said rows of protuberances, wrapping a sheet of material around said sleeve over said protuberances, and clamping said sheet to said tubes outside said protuberances. y

l0. A coupling for connecting together the juxtaposed ends of two tubes comprising raised portions annularly arranged on the outer peripheries of said tubes at different distances from said ends respectively, a sleeve closely surrounding said ends and extending outwardly to the saidraised portions on one of said tubes, the other of said raised portions being displaced :from the end of the other tube a sufficient distance to permit said sleeve to be moved along the other tube beyond the joint between the two tubes, a sheet of material wound around said sleeve and extending over said raised portions, and means for securing said sleeve to said tubes in the regions of said raised portions.

l1. A coupling for connecting together the juxtaposed ends of two tubes comprising raised portions annularly arranged on the outer peripheries of said tubes in spaced relationship to said ends, a sleeve closely surrounding said ends between said raised portions, one of said raised portions being spaced from the end of the tube a distance suicient to permit said sleeve to be moved along the tube beyond the joint between the` two tubes, and a sheet of material Wound around said sleeve and secured to said tube in the regions of said raised portions.

Signed by me at Dallas, Texas, this third day of February, 1919.

ALBERT W. PEARSALL. 

